The argument from illusion suggests that when we perceive objects in the external world, all we are ever directly aware of are sensory experiences as of objects and not the objects themselves. This leads to the problem of scepticism: if one is only ever directly aware of sensory experiences as of objects and not objects themselves, how can one know that the objects really are as they seem to be? One\'s beliefs about the external world go beyond one\'s immediate experience. So if one\'s beliefs about the external world are justified, they must be justified by inferences from the raw data of one\'s experience. One\'s beliefs about the external world have the status of hypotheses, and these hypotheses are justified by inferences from â€˜the givenâ€™: the raw data of one\'s experience. AJ

See also illusion, argument from; scepticism.Further reading J. Dancy, An Introduction to Epistemology; , J. Ross, The Appeal to the Given.